diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 905e90f2595756a1a4c56c6d068abfb3091d8c95..83b629b30c61283e17dfa371f016d9de0c73e901 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -921,9 +921,9 @@ struct i915_fbc { struct intel_fbc_work { bool scheduled; + u32 scheduled_vblank; struct work_struct work; struct drm_framebuffer *fb; - unsigned long enable_jiffies; } work; const char *no_fbc_reason; diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index a1988a486b9276954db36e8cb482db283a051887..3993b431b02a41e19cbaec3d64225ec748e606c7 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -381,7 +381,17 @@ static void intel_fbc_work_fn(struct work_struct *__work) container_of(__work, struct drm_i915_private, fbc.work.work); struct intel_fbc_work *work = &dev_priv->fbc.work; struct intel_crtc *crtc = dev_priv->fbc.crtc; - int delay_ms = 50; + struct drm_vblank_crtc *vblank = &dev_priv->dev->vblank[crtc->pipe]; + + if (drm_crtc_vblank_get(&crtc->base)) { + DRM_ERROR("vblank not available for FBC on pipe %c\n", + pipe_name(crtc->pipe)); + + mutex_lock(&dev_priv->fbc.lock); + work->scheduled = false; + mutex_unlock(&dev_priv->fbc.lock); + return; + } retry: /* Delay the actual enabling to let pageflipping cease and the @@ -390,14 +400,16 @@ static void intel_fbc_work_fn(struct work_struct *__work) * vblank to pass after disabling the FBC before we attempt * to modify the control registers. * - * A more complicated solution would involve tracking vblanks - * following the termination of the page-flipping sequence - * and indeed performing the enable as a co-routine and not - * waiting synchronously upon the vblank. - * * WaFbcWaitForVBlankBeforeEnable:ilk,snb + * + * It is also worth mentioning that since work->scheduled_vblank can be + * updated multiple times by the other threads, hitting the timeout is + * not an error condition. We'll just end up hitting the "goto retry" + * case below. */ - wait_remaining_ms_from_jiffies(work->enable_jiffies, delay_ms); + wait_event_timeout(vblank->queue, + drm_crtc_vblank_count(&crtc->base) != work->scheduled_vblank, + msecs_to_jiffies(50)); mutex_lock(&dev_priv->fbc.lock); @@ -406,8 +418,7 @@ static void intel_fbc_work_fn(struct work_struct *__work) goto out; /* Were we delayed again while this function was sleeping? */ - if (time_after(work->enable_jiffies + msecs_to_jiffies(delay_ms), - jiffies)) { + if (drm_crtc_vblank_count(&crtc->base) == work->scheduled_vblank) { mutex_unlock(&dev_priv->fbc.lock); goto retry; } @@ -419,6 +430,7 @@ static void intel_fbc_work_fn(struct work_struct *__work) out: mutex_unlock(&dev_priv->fbc.lock); + drm_crtc_vblank_put(&crtc->base); } static void intel_fbc_cancel_work(struct drm_i915_private *dev_priv) @@ -434,13 +446,20 @@ static void intel_fbc_schedule_activation(struct intel_crtc *crtc) WARN_ON(!mutex_is_locked(&dev_priv->fbc.lock)); + if (drm_crtc_vblank_get(&crtc->base)) { + DRM_ERROR("vblank not available for FBC on pipe %c\n", + pipe_name(crtc->pipe)); + return; + } + /* It is useless to call intel_fbc_cancel_work() in this function since * we're not releasing fbc.lock, so it won't have an opportunity to grab * it to discover that it was cancelled. So we just update the expected * jiffy count. */ work->fb = crtc->base.primary->fb; work->scheduled = true; - work->enable_jiffies = jiffies; + work->scheduled_vblank = drm_crtc_vblank_count(&crtc->base); + drm_crtc_vblank_put(&crtc->base); schedule_work(&work->work); }